The network has also decided to dedicate Mondays entirely to singing, with 'The Sing-Off' returning in the fall, followed by 'The Voice' at midseason. 'The Voice' will air from 8-10PM, before the debut of the Steven Spielberg-produced 'Smash,' about a group of people trying to put on a Broadway show based on the life of Marilyn Monroe. Emmy winner Debra Messing ('Will & Grace') stars.